UkrainTM, a semisynthetic Chelidonium majus alkaloid derivative, acts by inhibition of tubulin polymerization in normal and malignant cell lines

UkrainTM has been described as a semisynthetic Chelidonium majus alkaloid derivative, which exhibits selective toxicity towards malignant cells only. Its mechanism of action has hitherto been uncertain. We found that UkrainTM inhibits tubulin polymerization, leading to impaired microtubule dynamics. This results in activation of the spindle checkpoint and thus a metaphase block. The effects of UkrainTM on the growth, cell cycle progression and morphology of two normal, two transformed and two malignant cell lines did not differ. We could thus find no evidence for the selective cytotoxicity previously reported for UkrainTM.